In this session, we describe the acute phase in patients with metabolic syndrome from two sides; acute disease that occurs higher in patients with metabolic syndrome such as colonary heart disease and stroke, and acute aggravation of diabetes such as diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome. The electrolyte imbalance is frequently detected in critical ill patients. It is reported that the extreme abnormalities of ionized calcium concentrations are independent predictors of mortality. In addition, from clinical database MIMIC-Ⅱ,calcium supplementation improves clinical outcome in intensive care unit patients. Although metabolic syndrome; lifestyle-related disease, is a chronic disease, the possibility of falling into acute disease by having it becomes very high and improvement of electrolyte imbalance, especially hypocalcaemia is expected to effective on clinical outcome.